Embossing composition for preparing textured polymeric materials

ABSTRACT

A water-based embossing composition for use in chemically embossing a foamable polymeric material having a blowing agent incorporated therein comprising: (A) a film-forming resin dissolved or dispersed in said aqueous composition; (B) a modifier which is effective in modifying the activity of the blowing agent comprising particulate solids which are substantially insoluble and uniformly dispersible in the liquid medium of the embossing composition and which have an average particle size of no greater than about 100 microns, said modifier being present in the composition in an amount of at least about 3 wt. %; and (C) optionally, a colorant or a softening agent for the modifier solids or a mixture thereof.

This is a continuation of copending application Ser. No. 07/759,837,filed Sep. 13, 1991, now abandoned, which is a continuation of Ser. No.07/118,973 filed on Nov. 10, 1987, now abandoned.

FIELD OF THE INVENTION

This invention relates to an embossing composition for use in preparingchemically textured polymeric substrates, including use of the embossingcomposition for treating foamable polymeric compositions in theproduction of embossed, foamed polymeric substrates, especially texturedfloor coverings. In particular, the invention relates to anenvironmentally acceptable, aqueous-based embossing composition whichhas uniform embossing characteristics, good storage stability, and goodrheological properties. The embossing composition is especially suitablefor use in conjunction with standard apparatus for printing a foamablepolymeric composition.

The use of the embossing composition of the present invention isexemplified herein in connection with the production of foamed, texturedfloor coverings, especially vinyl sheet goods. The compositions are alsobroadly useful in a variety of other applications, as describedhereinbelow.

Embossing compositions for chemically embossing foamable polymericcompositions are well-known in the art. Such compositions were developedprimarily for use in the production of textured floor coverings andsimilar sheet materials, as described, for example, in U.S. Pat. No.3,293,094, issued to Nairn et al on Dec. 20, 1966, and incorporatedherein by reference. As disclosed in this patent, a foamed, texturedpolymeric material is produced from a foamable polymeric compositionhaving a blowing agent incorporated therein by selective application tothe surface of the composition of a modifier which affects the activityof the blowing agent in either a direct or an indirect fashion. Forexample, in a typical process for producing a textured floor covering, aplastisol containing a blowing agent is applied to a backing andheat-treated to convert the plastisol to a foamable composition usuallyreferred to as a "gel" under conditions which do not activate theblowing agent. An embossing composition containing a modifier for theblowing agent is applied to the gel, usually to selected portionsthereof in a predetermined pattern. This is accomplished typically byapplying the embossing composition to the gel by use of a rotogravureprinting cylinder.

Thereafter, the printed or coated gel is treated to activate the blowingagent which expands to effect differential foaming or expansion of thegel due to the presence of the modifier on selected portions of the gel.This results in the production of an embossed or textured pattern in thegel which is thereafter fused.

Modifiers having various functions are known, including modifiers whichpromote or inhibit activity of the blowing agent per se or which promoteor inhibit activity of a catalyst or accelerator which is admixed withthe blowing agent in the gel. Typically, the modifiers are patterned onthe gel as liquid formulations having the rheological characteristicsrequired for the particular application. The essential ingredients ofsuch liquid formulations are the modifier and a film-forming resin whichis dissolved or dispersed in the liquid phase of the formulation andwhich functions as a binder as the formulation dries. In addition, theformulation usually contains a colorant, for example, an ink, pigment ordye, which imparts color to the design of the textured pattern. Such aliquid formulation which comprises a modifier and a film-forming resinand optionally a colorant is known in the art as an "embossingcomposition" and is so referred to herein.

From the time that textured floor coverings of the aforementioned typewere first introduced to the marketplace (over 20 years ago) until thepresent, the only type of embossing compositions used commercially inthe U.S. to prepare such products have been and remain those based onthe use of a hydrocarbon liquid as a solvent and/or carrier for theother ingredients comprising the embossing composition. Such acomposition is referred to typically in the industry as an"organic-based embossing composition" and can comprise about 55 to about85 wt. % or more of the hydrocarbon liquid.

Although such compositions function well in the process formanufacturing textured floor coverings, there are concerns respectingthe effects such organic materials have on workers and on theenvironment into which they are discharged. Indeed, the concerns haveled to governmental regulations which control strictly the amount ofsuch materials that can be discharged into the environment. Althoughmany millions of dollars have been invested by the industry in equipmentfor reducing the amount of such organic materials discharged into theatmosphere, present day technology is such that it is not possible in apractical sense to avoid completely such discharge. It is believed thatcontinued discharge of organics is tolerated by environmentalists onlybecause a satisfactory alternative is and has not been available.

One alternative that has been explored involves substituting water forthe hydrocarbon liquid used in the embossing composition and it is tosuch water-based embossing compositions that the present invention isrelated.

REPORTED DEVELOPMENTS

The following patents disclose aqueous-based embossing compositions.

U.S. Pat. No. 4,083,907 and related U.S. Pat. No. 4,191,581, each toHamilton and assigned to the same assignee as the present invention,discloses an aqueous-based embossing composition having a pH of about 8to about 12 and containing: about 1 to about 15 wt. % of a modifier(referred to in the patent as a "foam-growth-controlling chemicalagent"); about 1 to about 9 wt. % of a water-soluble orwater-dispersible alcohol, for example, isopropanol; about 1 to about 11wt. % of a buffering agent, for example, ammonia; about 30 to about 75wt. % of an aqueous printing ink formulation; and about 10 to about 40wt. % of added water. Modifiers disclosed in this patent includetriazoles, for example, benzotriazole and various aminotriazoles. Suchcompounds are normally solid materials that are solubilized in thealkaline composition by the alcoholic constituent.

U.S. Pat. No. 4,369,065 and related U.S. Pat. No. 4,421,561 to Brixiusdiscloses an aqueous embossing composition having a pH of about 8 toabout 12 and containing: 1 to about 25 wt. % of a modifier, namely anorganic carboxylic acid containing 2 to 12 carbon atoms, an anhydride ofsuch acid, or an acid halide of such acid; about 3 to about 45 wt. % ofan aqueous printing ink formulation; about 1 to about 25 wt. % of abasic neutralizing agent, for example, ammonia; and about 1 to about 10wt. % of a pH controlling agent, for example, boric acid-sodiumtetraborate. The patent discloses that a particularly preferred modifieris trimellitic acid anhydride.

U.S. Pat. No. 4,407,882 to Hauser and Eckert discloses an aqueousembossing composition comprising: as a modifier, about 2 to about 20 wt.% of a particular type of azole (referred to in the patent as a "foaminhibitor"); 1 to 10 wt. % pigment; 15 to 40 wt. % of a thermoplasticresin, for example, poly(vinyl chloride); and 5 to 25 wt. % of anorganic solvent, for example, isopropanol.

Notwithstanding the developments described in the aforementionedpatents, the commercial use of aqueous-based embossing compositions hasbeen frustrated for a variety of reasons. Difficulty has beenencountered in solubilizing in the aqueous compositions modifiers inamounts sufficient to achieve concentrations of modifiers in theembossing compositions to adequately and effectively treat the areas tobe embossed. For example, some triazoles commonly employed as modifiersare substantially insoluble in acidic medium. Consequently, suchmodifiers are commonly used only in alkaline solution. Inasmuch ashighly alkaline solutions promote electrochemical attack on metalsfrequently used in embossing rolls, such solutions are not useful as apractical matter in these applications using this machinery.

Additionally, many known modifiers have limited solubility even inalkaline solutions. Accordingly, substantially uniform application ofthese modifiers from the embossing composition to the underlying blowingagent-containing gel in sufficiently high concentrations to provide awell-defined embossing effect cannot be achieved readily. Attempts havebeen made to promote solubility of these modifiers in both acidic andalkaline aqueous solutions by addition of organic solvents, especiallywater-miscible organic solvents such as lower (for example, C₁ -C₆)alkanols. Often, however, adequate solubilization of the modifier isonly achieved at the expense of optimum rheological characteristics.Typically, viscosity of the embossing composition is reduced below thatrequired for printing, necessitating the addition of thickeners.Thickeners, in turn, tend to interfere with printing characteristics toan extent determined by the particular components and substrate.

The aforementioned Hamilton, Brixius, and Hauser et al patents describeaqueous embossing compositions which comprise the modifier in solutionform. The Hamilton patent contains an additional disclosure that themodifier is also "dispersible" in the aqueous-alcoholic embossingcomposition, alcohol being an essential constituent of the Hamiltoncomposition. An analysis of all of the examples in the Hamilton patentshows that the modifier is present in each of the exemplified embossingcompositions in dissolved form. For this purpose, the weight proportionof solvent (alcohol) to modifier is relatively high, for example,falling within the range of 0.58 to 1.5 times as much solvent asmodifier or 37 to 60 wt. % of solvent based on the weight of the solventand modifier. The use of such compositions results in problems and isaccompanied by disadvantages of the type discussed above.

The present invention relates to improved environmentally acceptable,water-based embossing compositions which are capable of being usedindustrially with but relatively limited changes to presently usedmanufacturing lines, particularly rotogravure printing lines.

SUMMARY OF THE INVENTION

In accordance with the present invention, it has been found that animproved water-based embossing composition can be formulated by use of awater-insoluble modifier which is present in the composition in the formof fine solid particles of sufficiently small size to permit themodifier to be uniformly dispersed in the composition in an effectiveamount and in the absence of a material which is effective insolubilizing the modifier, for example, a solvent such as the alcoholicsolubilizing agent of the type referred to in the aforementionedHamilton and Hauser et al patents. In addition to modifier and water,another essential constituent of the composition of the presentinvention is a film-forming resin dissolved or dispersed in the aqueousmedium of the composition.

In preferred form, the water-based embossing composition of the presentinvention includes also a material which is effective in softening thesolid particles of modifier. Such a material, referred to herein as a"softening agent", improves various properties of the embossingcomposition, as is described hereinbelow, by rendering the particlesmalleable or pliable. The amount of softening agent in the compositionis small relative to the amount of particles of modifier, for example,about 25% or less of softening agent based on the total weight of thesoftening agent and modifier. Preferred softening agents include aminesand alcohols, the last mentioned being particularly preferred.

In accordance with another aspect of the present invention, there isprovided a water-based embossing composition for use in chemicallyembossing a foamable polymeric material having a blowing agentincorporated therein comprising:

(A) a film-forming resin dissolved or dispersed in the aqueous medium ofsaid composition;

(B) a modifier which is effective in modifying the activity of theblowing agent and which comprises particulate solids substantiallyinsoluble and uniformly dispersible in the liquid medium of theembossing composition and having an average particle size of no greaterthan about 100 microns, said modifier being present in the compositionin an amount of at least about 3 wt. %; and

(C) optionally, a colorant and/or softening agent.

The preferred modifier for use in the practice of the present inventionis a triazole, most preferably benzotriazole or tolyltriazole.

In particularly preferred form, the average particle size of themodifier is no greater than about 75 microns and is most preferably inthe range of about 40 to about 75 microns.

It is believed that the invention will be used most widely in connectionwith a composition that includes a colorant, and particularly one addedto the composition in the form of an aqueous printing ink.

In accordance with another aspect of this invention, there is provided amethod for preparing a foamable polymeric material capable of beingchemically embossed comprising:

(A) providing a foamable polymeric material comprising a resin and ablowing agent capable of effecting expansion of said material atelevated temperature;

(B) applying to predetermined portions of the surface thereof awater-based liquid embossing composition comprising a modifier which iseffective, as the treated material is heated, for modifying the activityof the blowing agent in those portions of the material to which theembossing composition is applied, said modifier being in the form offine solid particles of sufficiently small size to render the modifieruniformly dispersed in the liquid medium of said composition; and

(C) drying the embossing composition after it has been applied to saidsurface.

In preferred form, the method of the present invention involves thepresence in the foamable polymeric material of a blowing agent and anaccelerator for the blowing agent, and the use of a modifier whichrenders the accelerator at least partially ineffective.

The present invention provides numerous advantages relative to prior artmeans involving the use of water-based embossing compositions in themanufacture of textured articles. Such advantages flow from the use of ablowing agent modifier in finely divided solid form. The use of suchfinely divided particles permits the manufacturer to incorporaterelatively large amounts of the modifier in the embossing compositionwithout adversely affecting other desired properties of the compositionsuch as, for example, viscosity properties. This is important becausethere are applications where relatively high amounts of modifier areneeded (for example, in excess of 30% by weight of the composition).Another advantage of the present invention is that desired amounts ofthe modifier can be incorporated into the composition without having totake into account the pH of the composition. This gives the user muchgreater flexibility in selecting other constituents for use in thecomposition and greater flexibility in selecting manufacturingparameters.

Another important aspect of the present invention is that the embossingcompositions retain desired modifying properties for long periods oftime, typically at least about 2 months, as compared to prior artaqueous embossing compositions which may have storage stability of nomore than about 1 week. Developmental work has shown that suchproperties are retained for periods of many weeks and even as long assix months or more. In this connection, and by way of background, it isnoted that there are applications where there may be long periods oftime that pass between the making of the embossed foamable polymericmaterial and the time when the material is treated further to activatethe blowing agent and expand the material and convert it into a finishedproduct.

Experience has shown that various types of prior art embossingcompositions lose their modifying properties as they age, that is, themodifier tends to lose its ability to change the activity of the blowingagent. This limits the use of printed foamable polymeric material of thetype heretofore known. Such problems can be avoided by practice of thepresent invention.

The excellent stability properties of the embossing composition renderit highly suitable for use in a transfer printing process, a particulartype of heretofore known printing method, as described below.Accordingly, another aspect of the present invention encompasses atransfer printing sheet for use in a transfer printing process, saidsheet comprising a support sheet having adhered thereto in apredetermined pattern an embossing composition of the present invention,the support sheet being strippable from said composition. The long-termstability properties of the present embossing composition areparticularly advantageous and critically important to its use in atransfer printing sheet.

Other advantages which flow from the use of the present invention willbe appreciated from the following detailed description of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The essential ingredients of the liquid embossing composition of thepresent invention are: (A) water; (B) a film-forming resin dispersed ordissolved therein; and (C) a blowing agent modifier in finely dividedsolid form. Optionally, the embossing composition includes a colorantand conventional additives, and also a softening agent, which althoughoptional is a highly preferred constituent.

Many species of the film-forming resin and modifier for use in embossingcompositions of the present invention are known and have been proposedfor use in embossing compositions, for example, as described in each ofthe patents mentioned above. Building on such prior art disclosures, theunique aspects of the present invention can be used to advantage in avariety of embossing compositions of the type which can be used to printpatterns on the surface of foamable polymeric materials.

As known, the film-forming resinous constituent of the embossingcomposition functions as a binder for other ingredients comprising thecomposition. Typically, the film-forming resin will be present in thecomposition in dissolved form or, as is more typically the case, in theform of solid particles of resin which are dispersed in the composition.Latexes, that is, aqueous compositions containing solid particles ofresin dispersed in water are used widely in formulating embossingcompositions. Examples of film-forming resins which can be used in thepractice of the present invention include vinyl and acrylic resins suchas, for example, poly(vinyl chloride), poly(vinylidene chloride),copolymers of vinyl chloride and vinyl acetate, poly(vinyl alcohol),ethylene acid copolymers, polyacrylates, polymethacrylates, and polymersof acrylic acid and methacrylic acid, and also polyurethanes andmelamine resins. A mixture of film-forming resins can be used in theembossing composition.

As mentioned above, it is believed that the present invention will beused most widely in that form of composition which includes a colorant.However, there are applications where the embossing composition containsno colorant, in which case a clear film can be formed from thecomposition. As described below, a clear film can be formed from acommercial printing ink which is referred to in the industry as a"clear" or "reducing clear" which contains no colorant.

The modifier for use in the present invention is a material whichdirectly or indirectly affects the activity of the blowing or foamingagent in the foamable polymeric material which is contacted with theembossing composition. The modification of the activity of the blowingagent can be effected by having the modifier act directly on the blowingagent or on a material which itself has an influence on the blowingagent, for example, a catalyst, accelerator or inhibitor that is presentin the foamable polymeric material. It should be appreciated that theparticular modifier selected for use in an application will depend onthe particular blowing agent used in the foamable polymeric material orparticular catalyst, accelerator or inhibitor that may be used with theblowing agent. Such selection can be made in accordance with informationknown to those in the art. An extensive discussion of factorsinfluencing such selection appears in the aforementioned Nairn et alpatent.

The present invention encompasses the use of any modifier that issubstantially insoluble in the liquid medium of the embossingcomposition and that is capable of being reduced to a particle sizesufficiently small to enable the modifier to be uniformly dispersed inthe composition. The term "substantially insoluble" means that no morethan about 3 wt. % of the modifier is soluble in the water-based liquidmedium of the composition at room temperature (72° F.). Typically, thewater solubility of the modifier at room temperature is even lower, forexample, no greater than about 1 wt. %.

It should be appreciated that the solubility of materials in aqueousmedium can vary depending on the pH of the medium. One of thedisadvantages attendant with the use of prior art embossing compositionsis that compounds particularly suitable for use as modifiers do not havegood solubility characteristics at pH values that are advantageous touse. For example, it is more desirable to use a neutral or acidicembossing composition than an alkaline embossing composition in anapplication which involves the use of rotogravure printing cylindersbecause of the tendency of an alkaline composition to degrade the metalcomprising such cylinders. However, particularly effective modifierssuch as triazoles have poor solubility properties in an acid to neutralembossing composition, and accordingly, the proposed use of suchmodifiers in soluble form in accordance with prior art teachings isrestricted to alkaline embossing compositions. To obtain the desiredsolubility properties, while making efforts to avoid degradation of thecylinders, requires the exercise of careful control and implementationof special techniques. Such requirements dictate against industrial use.

Pursuant to the present invention, it is not necessary to take intoaccount the pH of the embossing composition in connection with theeffective incorporation of the modifier into the embossing composition.Accordingly, the pH value of embossing compositions of the presentinvention can vary over a broad range and from acidic to basic.

Reference is made to the aforementioned Nairn et al patent (U.S. Pat.No. 3,293,094) which contains an extensive description of compounds ofthe type that can be used to modify the "blowing" properties of ablowing agent which is present in a foamable resinous composition fromwhich an embossed, foamed, polymeric article can be made. Such compoundis referred to in this patent as a "regulator" or an "inhibitor". Theterm "modifier", as used herein, encompasses compounds of the type whichfunction in the manner described in the Nairn et al patent.

The Nairn et al patent discloses also that the particular modifierselected for use in an application depends on the nature of the blowingagent or of the blowing agent system that is used and sets forthguidelines for selection. Among the classes of compounds disclosed byNairn et al for use as modifiers in embossing compositions are thefollowing: organic acids, for example, those containing at least twocarboxyl groups or those having at least one carboxyl group and onehydroxy group and which contain 2-12 carbon atoms; organic acid halidesand anhydrides, for example, those which contain 2-20 carbon atoms;polyhydroxy alcohols, for example, polyhydroxy aromatic compounds whichcontain 2 hydroxy groups and up to 20 carbon atoms; nitrogen-containingcompounds, for example, amines, amides, and oximes; sulphur-containingcompounds, for example, thiols, mercaptans, sulfides, sulfones,sulfoxides, sulfonic acids, sulfonyl chloride; suolfonamides, andsulfimides; isocyanates, for example, mono- and di-isocyanates; ketonesand aldehydes; for example, those containing two functional groups; andphosphate and phosphite compounds. The Nairn et al patent disclosesstill additional examples of modifiers of a miscellaneous type, forexample, at Column 17, lines 11-55. Modifiers which are described asbeing particularly useful in water-based embossing compositions are thesubject of the aforementioned Hauser et al patent. The modifiersdisclosed in this patent are azoles of a particular type.

Preferred modifiers for use in accordance with the present inventioninclude: triazoles, including aminotriazoles, azoles, hydroquinone andthiourea.

In preferred form, the present invention comprises the use of a modifierwhich is effective in indirectly modifying the activity of the blowingagent by reducing at least partially the effectiveness of an acceleratorwhich is present as a constituent of the blowing agent system present inthe composition comprising the foamable polymeric material. Anaccelerator can function in various ways to modify the activity of theblowing agent. For example, it can accelerate decomposition of theblowing agent, or it can reduce the temperature at which the blowingagent decomposes, or it can narrow the temperature range over which theblowing agent decomposes to reduce the temperature at which the blowingagent is activated.

A highly preferred modifier/blowing agent system recommended for use inthe practice of the present invention comprises benzotriazole ortolyltriazole as the modifier and a blowing agent system which includesazodicarbonamide as the blowing agent and zinc oxide as the accelerator.

With respect to particle size of the modifier, the minimum size of theparticles is determined basically by considerations associated withhaving the modifier present in the composition in solid form and withthe practicalities and economics of making the modifier in a fine sizeform which is dispersible, but not soluble. With respect to maximumsize, the finely-divided modifier should be capable of forming arelatively stable and uniform suspension or dispersion in thecomposition to permit substantially uniform application of modifier tothe surface of the foamable polymeric material as the embossingcomposition is applied thereto via the desired printing means. For aparticular modifier and/or particular application, maximum and minimumparticle size can best be determined by empirical means. It is believedthat many applications will benefit by the use of a modifier having anaverage particle size of no greater than about 100 microns. Based onpresent work, it is preferred that the average particle size of themodifier be not greater than about 75 microns, for example, about 10 toabout 75 microns, and most preferably, the average size is within therange of about 40 to about 75 microns.

The modifier can be incorporated into the composition in various ways.For example, coarse particles of the modifier can be milled into areducing clear to form a viscous liquid or thick paste, depending on theamount of modifier used. This concentrate of resin and modifier can thenbe used to prepare the desired embossing composition by admixingtherewith pigments and other desired ingredients. A clear embossingcomposition can be prepared by adding to the modifier/clear concentrateadditional resin in an amount sufficient to produce the desired finalcomposition. Alternatively, coarse particles of modifier can besubjected to a micronizing process to reduce the size of the particlesto the desired fineness. The modifier in fine powder form can then beadded directly to and mixed with the other ingredients comprising theembossing composition.

As mentioned above, an optional but highly preferred constituent of thepresent invention is a softening agent which functions to render thesolid particles of modifier pliable or malleable. The use of thesoftening agent improves the printing qualities of the embossingcomposition. It is believed that such improvements are achieved at leastin part because the pliable particles can be squeezed more effectivelyinto the cells of printing cylinders. This improves the uniformity ofthe application of the embossing composition to the foamable gel. It hasbeen observed also that the use of the softening agent avoids streakingof the embossing composition after it has been contacted with a doctorblade of the type used in conventional printing apparatus.

In addition, the flow properties of the embossing composition aregenerally improved as a result of the use therein of the softeningagent.

Typically, the softening agent is a liquid material which is soluble ormiscible in the liquid phase of the embossing composition, and isabsorbable by the solid particles of modifier. The absorbed softeningagent tends to swell the solid modifier particles. Examples of softeningagents that can be used are amines and alcohols, the last mentionedclass of compounds being preferred. Preferred alcohols for the use ofthe practice of the present invention contain 1 to about 6 carbon atoms,for example, methanol, ethanol, propanol, butanol, pentanol, andhexanol, including various of the isomers thereof. Examples of aminesthat can be used include alkylamino-alcohols, exemplary of which are2-dimethylaminoethanol, 2-methylaminoethanol and 2-ethylaminoethanol.Other hydrocarbon miscible or soluble liquids which do not adverslyaffect the composition or the printing/embossing process and whichfunction to soften the modifier particles can be used also.

The use of such softening agents should be distinguished from the use ofalcohols and other "modifier" solvents as disclosed in the prior art,for example, the aforementioned Hamilton and Hauser et al patents. Inthe techniques of the prior art, alcohols and other materials which areeffective modifier solvents are used in amounts sufficient to dissolvethe normally solid compounds which function as modifiers. To effectdissolution of the modifiers, the weight proportion of solvent tomodifier is relatively high. For example, in the specific compositionsdisclosed in the Hamilton patent, alcohol comprises 37-60 wt. % of thetotal amount of alcohol and modifier. Furthermore, the compositionsshown in the example section of the Hamilton patent include aminohydroxycompounds which aid in effecting dissolution of the modifier.Accordingly, such compositions comprise a high proportion of organicsolvating materials relative to the amount of modifier. Conversely, thecompositions described in the Hamilton patent have a relatively smallratio of modifier to alcohol, for example, such compositions containingabout 0.7 to 1.7 times as much modifier as alcohol.

In contrast to the teachings of the prior art, the use of softeningagents in accordance with the present invention, including thosecompounds which function in sufficiently high amounts as a solvent forthe modifier, comprises an amount which is not effective in dissolvingthe modifier. For this purpose, the maximum amount of softening agentrelative to the amount of modifier is relatively small. Inasmuch as thesolvent effect of softening agent on modifier will vary from onesoftening agent to the next, amounts for use in the practice of thepresent invention can best be determined for any particular combinationof softening agent/modifier by evaluating the effect that the liquidsoftening agent has on the solid modifier, taking into account thefollowing guidelines. Speaking generally, any perceptible softening ofthe solid particle of modifier tends to result in improvements so thatthe minimum amount of softening agent can be that which is effective insoftening the solid particles. When using a softening agent which isalso a solvent for the modifier, the maximum amount of softening agentis an amount less than that which causes dissolution of the solidparticles in the water-based composition. Otherwise, the maximum amountcan be dictated by a levelling off of improvements or adverse effectswhich may be encountered. As a further guideline, it is recommended thatthe amount of softening agent comprise at least about 1 wt. % of thecomposition based on the total weight of the composition, and that thecomposition contain at least about 3.5 times as much modifier assoftening agent. For most applications, it is believed that it will notbe necessary to use more than about 5 wt. % of the softening agent basedon the total weight of the composition. In preferred form, the softeningagent comprises about 2 to about 4 wt. % of the total weight of thecomposition, and the composition includes at least about 5 times as muchmodifier as softening agent. It should be understood that variations inthe foregoing amounts may need to be made for a particular softeningagent/modifier combination for reasons mentioned above.

It should be appreciated that by using the softening agent in therelatively small amounts described herein, there are achieved not onlyfunctional improvements in the printing process, but there are avoidedvarious problems associated with the use of the high proportions ofsolvent according to prior art teachings. For example, in connectionwith the use of an alcohol solvent as described by Hamilton, alcohol canfunction to significantly depress the viscosity of the embossingcomposition causing it to become thin, this in turn causing it toproduce a wormy, printed image of poor resolution. Various of thealkanolamines that are disclosed in the aforementioned Hamilton patentcan function to slow the drying of the embossing composition. Tocompensate for this, it is necessary to decrease the line speed of theprinting operation. Such undesirable characteristics and adjustments canbe avoided by practice of the present invention.

As mentioned above, it is believed that the present invention will beused most widely in connection with embossing compositions which containa colorant, for example, in the form of a pigment (inorganic or organic)or dye. Inasmuch as the composition of the present invention can be usedeffectively as either an acidic or an alkaline composition, as describedmore fully below, a wide variety of colorants can be used. Thus, theacid or alkaline sensitivity of the colorant for use in embossingapplications becomes much less, if any, a factor, in the practice of thepresent invention than is the case with prior art water-based embossingcompositions.

Examples of pigments that can be used as the colorant are phthalo blue,phthalo green, scarlet red, carbon black, titanium dioxide, zincsulfide, cadmium sulfide, iron oxide, perionone, and disazo yellow.Examples of dyes that can be used as the colorant are basonyl red-NB540, neozapon yellow 108, neozapon black X51, and neozapan blue 807.

Colorant-containing embossing compositions and also embossingcompositions for use in forming a clear film are typically formulatedfrom a "printing ink" which is usually a proprietary composition sold tothe floor covering industry by an ink manufacturer, for example:American Ink Co., Carolina Inks Co., Custom Chemicals, Inc., Gotham Co.,GPI-Sun Corp., Inmont Co., Lenape Co., Polytex Corp., RBH Dispersions,Sinclair & Valentine Corp., Strahan Co., and Visol Corp. Printing inksfor use in forming a colored film generally comprise an admixture ofpigment, film-forming resin solids and water. Clear embossingcompositions are conveniently formulated from a commercial printing ink,which as mentioned above, is referred to in the industry as "clear" or"reducing clear" containing no colorant. Colored embossing compositionsare conveniently based on clear embossing compositions by incorporationof a colorant. Additives are usually present also in the printing ink,for example, surfactants and emulsifying agents.

For use in the present invention, the printing ink is a water-basedcomposition, and when used, it is a source of at least a portion of thefilm-forming resin and water constituent of the composition, as well asa source of colorant. Such aqueous printing inks may contain arelatively small amount of hydrocarbon liquid, for example, alcohols ormore highly potent organic solvents such as ethers or esters. Asmentioned above, such hydrocarbon liquids comprise a relatively smallproportion of the composition of the present invention, for example, nogreater than about 5 wt. % based on the total weight of the composition,but in no event is such liquid present in an amount which wouldsolubilize the modifier.

The amounts of the aforementioned essential and optional constituentscomprising the composition can vary over a wide range. The amount offilm-forming resin should be at least sufficient to provide the bindingeffect that is desired. The amount of modifier should be at leastsufficient to provide the desired change in activity of the blowingagent. And the amount of colorant should be that needed to provide thedesired color or shading to the pattern printed in the textured surface.The amount of softening agent has been discussed hereinabove.

For achieving the aforementioned, it is recommended that the compositioncomprise at least about 10 wt. % of the film-forming resin and at leastabout 3 wt. % of the modifier, and that the colorant and softeningagent, when used, comprise respectively at least about 3 wt. % and 1 wt.% of the composition. It is believed that the following formulation willbe effective for use in most applications: (A) about 10 to about 40 wt.% of the film-forming resin; (B) about 3 to about 40 wt. % of themodifier; (C) 0 to about 45 wt. % colorant; (D) 0 to about 5 wt. % ofsoftening agent; and (E) about 10 to about 40 wt. % water, and when asoftening agent is used, the amount of modifier should be at least about3.5 times the amount of softening agent.

The composition of the present invention can include one or moreadditives that can be added directly to the composition or as anassociated constituent of the film-forming resinous constituent or ofthe colorant constituent. Some examples of such additives includeplasticizers, stabilizers, dispersion aids, drying aids,viscosity-control additives, buffering agents, pH adjusters, coalescingagents and emulsifying agents. The amount of any one of such additiveswill typically not exceed about 2.5 wt. %, the total amount of theadditives generally being no greater than about 5 wt. %, based on thetotal weight of the embossing composition.

As mentioned above, one of the advantages of the present invention isthat it is capable of being formulated in a stable state over a broad pHrange. For most applications, it is believed that a pH within the rangeof about 6.5 to about 12 will be satisfactory. It is preferred that thepH of the composition be about 6.5 to about 9. The pH of the compositioncan be adjusted, if necessary, by use of mineral acids or alkali metalhydroxides.

According to the invention, embossing compositions described herein canbe formulated at a viscosity level which permits the composition to beused in a variety of applications. As previously noted, the compositionsare particularly suitable for use in rotogravure applications in whichthe embossing composition is patterned onto a foamable gel byrotogravure printing cylinders. These cylinders have been long used forprinting organic-based embossing compositions and represent a majorcapital investment to the industry. In these applications, cylindersstudded with printing cells of a typical depth of from about 50 to about60 microns are used to apply organic-based embossing compositions to thesubstrates comprising foamable gels. Such cylinders cannot be usedeffectively with aqueous-based embossing compositions as a practicalmatter because the amount of time required to evaporate water from thefilm applied to the substrate is much longer than the time required toevaporate typically used organic solvents. In order to afford sufficienttime for evaporation from the film of the water constituent, it ispossible, but not desirable, to decrease the speed of the printing line.In an effort to avoid or offset this problem, the depths, and thereforethe volumes, of the printing cells can be decreased so that a lesseramount of embossing composition, and thus less water, is printed ontothe substrate. The smaller the amount of water, the shorter the dryingtime. However, this approach to the problem requires the use of higherconcentrations of modifiers in the aqueous-based embossing compositionso that application of the composition from the modified (smallervolume) cylinders applies the same amount of modifier onto the foamablegel for acceptable embossing effects. At alkaline pH, however, therequisite amount (typically 15-30 wt. %) of popularly used modifiers,such as benzotriazole, cannot be dissolved in the aqueous-basedcomposition, except by use of solubilizing agents, usually organicsolvents such as lower alcohols, as described in the aforementionedHamilton patents. Unfortunately, the use of such solubilizing agentsresults in embossing compositions having viscosities unacceptably lowfor rotogravure printing, typically below about 100 cp (Brookfield @74°F.). Experience has shown that in order to avoid problems that areencountered when using such low-viscosity compositions in rotogravureprinting, the viscosity thereof should be at least about 600 cp, andpreferably are at least about 700 cp (each Brookfield at 74° F.).Attempts to increase the viscosities of aqueous-based compositionscontaining organic liquid solubilizing agents to acceptable levels forthis and comparable applications have been largely unsuccessful. Forexample, the use of thickeners has typically resulted in poor-qualityembossing compositions.

The present invention overcomes these difficulties by an entirely newapproach. Compositions according to the invention containing relativelyhigh concentrations of modifier (for example, about 15 to about 30 wt.%) in finely-divided particle form can be formulated readily withviscosity values in the range of about 600 to about 1000 cp. And thiscan be accomplished without having to add viscosity modifiers to thecomposition to increase the viscosity to acceptable levels. Accordingly,compositions within the scope of the present invention are entirelysuitable for rotgravure applications in which cylinders of relativelyshallow cell depth are employed. For example, such compositions areuseful in embossing processes employing electromechanically engravedcylinders having cell depths of about 18 to about 42 μ because they canbe formulated to contain a relatively high concentration of modifier,for example, at least about 17 wt. % and ranging up to about 30-40 wt.%. Normal printing speeds (for example, about 150 to 300 feet perminute) are thereby attainable. In general, the shallower the depth ofthe cell, the higher should be the concentration of the modifier.

If there are applications for which higher viscosity compositions areneeded, conventional thickeners, for example, amorphous silica gel, canbe usefully added in an amount sufficient to obtain the desiredviscosity.

The foamable polymeric material to which the water-based embossingcomposition of the present invention is applied comprises a resin and ablowing agent, with or without accelerator or inhibitor. Poly(vinylchloride) is the most popularly used resin in the industry, althoughthere can be used other resins such as, for example, other vinylchloride polymers, including copolymers thereof, and resins such aspolyurethanes, polystyrenes and polyamides. The foamable polymericmaterial is preferably made from a plastisol which comprises resinsolids dispersed in liquid plasticizer. Examples of plasticizers includedioctyl phthalate, butyl benzyl phthalate, di-(2-ethyl hexyl) phthalateand tricresyl phosphate. The blowing agent, which is a compound thatliberates an inert gas upon being heated, is typically azodicarbonamide,this being a widely used blowing agent in industry. However, inaccordance with knowledge in the art, there can be used other blowingagents, for example, bis-(p-hydroxybenzenesulfonyl) hydrazide,azobisisobutyral-nitrile and diazoaminobenzene. As previously noted, theblowing agent can be combined with an accelerator or inhibitor whichmodifies the properties of the blowing agent. Examples of such materialsinclude zinc oxide, dibasic lead phosphate, and zinc octoate.

In its most widely used form, the foamable polymeric material isprepared from a composition comprising a blowing agent system and one ormore resins dispersed in a liquid medium, for example, a plastisol. Theaforementioned Nairn et al patent contains an extensive discussion ofthe preparation of such foamable materials and cites numerous examplesof resins, plasticizers, and blowing agents and materials which have aneffect on the blowing agent.

For use as a flooring material, the liquid resin composition comprisingthe blowing agent and plastisol and optional ingredients, for example,fillers, pigments, and stabilizers, is then usually applied to asubstrate which functions as a carrier or backing for the composition.Such a substrate can comprise a felt material, a polymeric material or afiber-reinforced material, including, for example, fibers of asbestos,glass, and natural and synthetic fibers. After the liquid resincomposition is applied to the substrate, the resulting composite isheated to a temperature sufficiently high to gel the liquid, but at atemperature below that at which the blowing agent is activated.

The embossing composition of the invention can be applied in anappropriate design to the gelled foamable polymeric material to achievethe desired visual effect. Several applications are customary formulticolored effects. The composition may be applied in separate runswithout modifier or with a clear embossing composition to respectivelycolor areas without embossing or to emboss areas without coloring.

As disclosed in the aforementioned Nairn et al patent, it is alsopossible to prepare the embossed article by applying the embossingcomposition to a supporting base or on the underside of a layer of thefoamable composition.

Although the composition of the invention is particularly adapted toapplication by rotogravure techniques, other printing methods,including, for example, off-set gravure, flexographic processes, screenprinting or relief printing, can be used also. The present invention canbe used also to excellent advantage in the fabrication of a "transfersheet" for use in a transfer printing process of the type describedimmediately below.

The aforementioned description of the use of the present inventionentails the initial application of the involved compositions directly tothe surface of the foamable polymeric material. For use in a transferprinting process, the compositions are not applied initially to thefoamable polymeric material, but instead to the surface of a supportsheet. The support sheet, having printed thereon the embossingcomposition in predetermined fashion, is known as a "transfer sheet"which can be used by superposing it on the foamable polymeric materialin a manner such that the embossing composition is contacted with thesurface of the polymeric material. Thereafter, the support sheet ispeeled away or stripped from the surface of the foamable compositionleaving thereon the embossing composition in the desired pattern.Typically, heat and pressure are applied to the multi-ply structurecomprising the support sheet having thereon the embossing compositionand the foamable composition to ensure transfer of the embossingcomposition from its support sheet to the surface of the foamablecomposition. An example of a transfer printing process of this type isdescribed in U.S. Pat. No. 4,482,598, the disclosure of which isincorporated herein by reference.

There are various factors which provide incentives for use in industryof the transfer printing process in the manufacture of textured floorcoverings and the like. By way of background, it is noted thatrotogravure printing cylinders which are used in the rotogravure processfor applying embossing compositions of the type described herein arerelatively expensive. Accordingly, there is an economic advantage tobeing able to utilize such printing cylinders to apply embossingcompositions to transfer sheets which can be shipped more economicallythan final product to distant sites where the transfer sheet can be usedto make final product. Stated simply, use of a transfer sheet of thetype described herein permits a manufacturer to make the ultimateproduct without having to invest in printing facilities and printingcylinders which can comprise a high proportion of the overall investmentneeded to make final product.

Although the transfer printing process of the type described above hasbeen known for several years, it has not been capable of being usedeffectively with heretofore known water-based embossing compositionsbecause such compositions, otherwise effective for practical use, havebeen unstable. The modifier in the embossing composition loses itseffectiveness.

As mentioned above, embossing compositions within the scope of thepresent invention can be formulated in a form which is highly stableover extended periods of time, including many months. This enables aparty to fabricate a transfer sheet and ship it, for example, by lowcost ocean freight to countries where moneys for capital investment areat a premium. There it can be used in the manufacture of floor coveringsor similar products which otherwise might not be made because of thehigh capital investment needed for the manufacture and purchase ofrotogravure facilities printing cylinders.

Turning now to a more detailed description of the transfer printingsheet of the type to which the present invention relates, it comprisestwo essential components, namely, a support sheet and adhered to thesurface thereof an embossing composition of the present invention in adesired pattern. It is believed that the transfer sheet will be usedmost widely in a form which includes also a release layer sandwichedbetween the support sheet and the embossing composition. Such releaselayer permits the support sheet to be more readily peeled or strippedfrom the transfer sheet leaving behind the embossing composition on thesurface of the foamable polymeric composition.

Any suitable material can be used for the support sheet, including, forexample, plastic film, metal foil or a paper or paper-like material.Examples of such materials include polyethylene, polypropylene,polystyrene, poly(vinyl chloride), and kraft paper.

The release layer, if used, can be formulated in accordance withtechniques available in the art. For example, the release layer can beformed from a composition comprising a release agent, for example, a waxor silicon, and a liquid carrier for the release agent, for example, anaqueous dispersion of resin solids (latex) or a cellulose derivative.Examples of such materials include latices of styrene or acrylic resins,or cellulose acetate or ethyl cellulose. The composition used to formthe release layer can include also additives, for example, plasticizer,filler, or surfactant.

The release composition can be applied to the support sheet by anysuitable means, for example, spray, brush, or roll coating, orextrusion. The amount of release composition applied to the supportlayer is that sufficient to form a release layer of desired thickness,for example, about 1 to about 50 microns.

The embossing composition can be applied to the surface of the supportsheet or to the surface of the release layer when it is used by the useof a rotogravure printing cylinder or by other suitable means.

After the transfer sheet has been superposed in contact with the surfaceof the foamable polymeric composition, transfer of the embossingcomposition from the transfer sheet to said surface is generallyeffected by application of heat and pressure to the composite structure.In general, there are used relatively low temperatures and pressures,for example, pressures of about 8 to about 70 kg/cm² and temperatures ofabout 150°to about 220° C. depending on the apparatus used. Suchapparatus can comprise a pair of opposing rolls, one of which is aheated roll or a heated press.

After transfer of the embossing composition to the surface of thefoamable polymeric composition and removal of the support sheet, thepolymeric composition can be heated to effect foaming and embossingthereof according to available techniques.

Various modifications to the aforementioned transfer printing processcan be made to achieve desired results. For example, as described inaforementioned U.S. Pat. No. 4,482,598, a purely decorative pattern mayalso be applied to the transfer sheet in addition to the embossingcomposition.

Examples which follow are illustrative of the practice of the presentinvention.

EXAMPLES Example No. 1

An embossing composition according to the invention was formulated froma commercially available, film forming resin (W-B Clear 59-995,available from RBH Dispersions) and tolyl triazole micro-Jet powder, asmodifier, by first admixing the resin clear and amorphous silica gel(dispersing/anti-blocking agent, sold under the trademark SYLOID 308 byDavison Chemical) and adding to the resulting mixture the tolyl triazolemicro-jet powder (average particle size 75 μ) with agitation for 12 to15 minutes. A fluorescing agent (optical brightener), sold under thetrademark LEUCOPHOR BMB by Sandoz, was added for the purpose ofhighlighting defects that might be present in the product. Thecomposition included also a viscosity modifier (chemical identityunknown) supplied by RBH Dispersions.

The resulting embossing composition comprised the following:

    ______________________________________                                        Component        % by Weight                                                  ______________________________________                                        film-forming resin                                                                             33.1                                                         tolyl triazole   25.0                                                         silica gel       2.5                                                          fluorescing agent                                                                              0.2                                                          isopropyl alcohol                                                                              4.0                                                          diethylaminoethanol                                                                            1.0                                                          viscosity modifier                                                                             0.2                                                          surfactants      1.0                                                          water            33.0                                                                          100.0                                                        ______________________________________                                         The viscosity of the composition was 860 cp (Brookfield @ 74° F.).     Unless stated otherwise, viscosity values herein are Brookfield @             74° F.                                                            

The next two examples also show embossing compositions within the scopeof the present invention. They are similar to the composition of ExampleNo. 1.

Example No. 2

    ______________________________________                                        Component        % by Weight                                                  ______________________________________                                        film-forming resin                                                                             39.00                                                        tolyl triazole   12.50                                                        silica gel       2.50                                                         fluorescing agent                                                                              0.25                                                         isopropyl alcohol                                                                              4.66                                                         diethylaminoethanol                                                                            1.27                                                         surfactants      1.27                                                         water            38.55                                                                         100.00                                                       ______________________________________                                         The viscosity of the composition was 800 cp.                             

Example No. 3

    ______________________________________                                        Component        % by Weight                                                  ______________________________________                                        film-forming resin                                                                             31.05                                                        tolyl triazole   30.00                                                        silica gel       2.50                                                         isopropyl alcohol                                                                              3.72                                                         diethylaminoethanol                                                                            1.00                                                         surfactants      1.00                                                         water            30.73                                                                         100.00                                                       ______________________________________                                         The viscosity of the composition was 850 cp.                             

Example No. 4

The next example shows an embossing composition of the present inventionwhich is similar to the compositions of Example Nos. 1 to 3, but itincludes a different modifier. The average particle size of the modifieris the same as that of the modifier of Example Nos. 1 to 3.

    ______________________________________                                        Component        % by weight                                                  ______________________________________                                        film-forming resin                                                                             35.65                                                        benzotriazole    20.00                                                        silica gel       1.95                                                         isopropyl alcohol                                                                              4.25                                                         diethylaminoethanol                                                                            1.15                                                         surfactants      1.15                                                         water            35.85                                                                         100.00                                                       ______________________________________                                         The viscosity of the composition was 800 cp.                             

The next three examples are illustrative of colorant-containingembossing compositions of the present invention. They were prepared byadding pigments to the composition of Example No. 2. The sources of thepigments were pigment pastes which are proprietary to the sellerthereof, namely RBH Dispersions.

    ______________________________________                                                      EXAMPLE NO.                                                                   5        6       7                                              ______________________________________                                        Constituents, wt. %                                                           composition of Ex. No. 2                                                                      97.84      98.37   99.00                                      red pigment paste                                                                             0.90       0.30    0.40                                       yellow pigment paste                                                                          0.68       0.47    0.43                                       black pigment paste                                                                           0.58       0.86    0.17                                       Properties                                                                    pH              7.51       8.17    7.9                                        viscosity, cp @ 80° F.                                                                 790        820*    800                                        ______________________________________                                         *measured @ 82° F.                                                

The composition of Example No. 2 from which the embossing inks ofExample Nos. 5 to 7 were prepared was stored for two months prior to itsbeing used as the base material for the preparation of the inks. Thecomposition remained stable during this storage period. The embossinginks prepared from the stable composition are capable of being usedeffectively in embossing applications as manifested by the effectivenessof the modifier in deactivating a zinc oxide accelerator associated withazodicarbonamide blowing agent in a gelled poly(vinyl chloride)composition plasticized with dioctylphthalate.

The next example shows an additional colorant-containing compositionwithin the scope of the present invention. The film-forming resin of thecomposition and the sources of the pigment and other constituents arethe same as those of the compositions of the previous examples.

Example No. 8

    ______________________________________                                        Component         % by Weight                                                 ______________________________________                                        film-foaming resin                                                                              35.50                                                       tolyl triazole    17.53                                                       silica gel        2.44                                                        fluorescing agent                                                             isopropyl alcohol 4.24                                                        diethylaminoethanol                                                                             1.16                                                        white pigment paste                                                                             1.50                                                        red pigment paste 0.40                                                        yellow pigment paste                                                                            0.45                                                        black pigment paste                                                                             0.25                                                        surfactant        1.17                                                        water             35.06                                                                         100.00                                                      ______________________________________                                         The viscosity of the composition was 850 cp (80° F.) and the pH        thereof was 8.1                                                          

The compositions of Example Nos. 1 and 8 above were used to emboss afoamable polymeric material having the formulation set forth below andbeing of a high gauge laboratory construction.

Foamable Polymeric Material

    ______________________________________                                        Foamable Polymeric Material                                                                        Parts by Wt.                                             ______________________________________                                        poly(vinyl chloride) - dispersion grade,                                                             31.0                                                   inherent viscosity 0.89                                                       poly(vinyl chloride) - dispersion grade,                                                             17.0                                                   inherent viscosity 0.88                                                       butylbenzyl phthalate plasticizer                                                                    19.0                                                   di-(2-ethyl hexyl)phthalate plasticizer                                                              8.5                                                    calcium carbonate filler                                                                             19.0                                                   aromatic petroleum solvent                                                                           1.5                                                    (boiling range 183-210° C.)                                            azodicarbonamide blowing agent/zinc oxide                                                            4.0                                                                           100.0                                                  ______________________________________                                    

The foamable polymeric material was gelled by heating at a temperatureof about 300° F. for about 3 minutes. A portion of the surface of eachof two gel samples was then printed with the composition of Example No.1 and with the composition of Example No. 8 using an electronicallyengraved proof plate with 150 lines per inch (lpi) and a cell depth of28 microns. A poly(vinyl chloride) wear layer was then applied to eachof the printed gel samples. Each was then heated to a temperature ofabout 390° F. for about 2 minutes to decompose the blowing agent andfuse the composite material.

Measurements of each of the samples showed the following.

    ______________________________________                                                     Samples Treated With                                                          Composition of                                                                Example No. 1                                                                           Example No. 8                                          ______________________________________                                        foam (gauge in mils)                                                                         53.8        53.9                                               wearlayer      14.8        15.0                                               embossed foam  -15.5       -23.7                                              embossed depth 38.3        30.2                                               ______________________________________                                    

The above results show that satisfactory embossing of a premiumconstruction can be achieved with shallow engraved printing plates atthe modifier concentrations used.

As mentioned above, the present invention can be used to particularadvantage in the production of foamed textured floor coverings. Itshould be understood that it can be used also to produce a variety ofother kinds of products having a foamed and textured or embossedstructure, including, for example, wall and ceiling coverings, table topand shelf coverings, automotive panels, book covers and decorativecontainers.

In summary, it can be said that the present invention provides apractical and functionally-effective means for industry to avoid the useof problem-causing hydrocarbon liquids by allowing a manufacturer tosubstitute in an industrial operating line, with relatively low capitalinvestment, the use of a water-based embossing composition for anorganic-based embossing composition. In addition, the excellentstability of the embossing composition of the present invention, evenunder poor storage conditions such as high humidity, makes the use ofaqueous-based embossing compositions in transfer printing practical forthe first time.

I claim:
 1. A water-based embossing composition for use in chemicallyembossing a foamable polymeric material having a blowing agentincorporated therein comprising:(A) a film-forming resin dissolved ordispersed in said aqueous composition; (B) a modifier which is effectivein modifying the activity of the blowing agent comprising particulatesolids which are substantially insoluble and uniformly dispersible inthe liquid medium of the embossing composition and which have an averageparticle size of no greater than about 100 microns, said modifier beingpresent in the composition in an amount of at least about 3 wt. %; and(C) optionally, a colorant; and wherein said modifier is present in thecomposition in the absence of a material which is present in an amountwhich is effective in solubilizing the modifier.
 2. A compositionaccording to claim 1 wherein the average particle size of said modifieris no greater than about 75 microns.
 3. A composition according to claim2 wherein said particle size is about 10 to about 75 microns.
 4. Acomposition according to claim 3 wherein said particle size is about 40to about 75 microns.
 5. A composition according to claim 1 wherein themodifier is benzotriazole or tolyl triazole.
 6. A composition accordingto claim 1 having a viscosity of about 600 to about 1000 cps.
 7. Acomposition according to claim 1 having a pH of about 6.5 to about 12.8. A composition according to claim 7 having a pH of about 6.5 to about9.
 9. A composition according to claim 1 including at least about 10 wt.% of said resin and at least about 3 wt. % of said colorant.
 10. Acomposition according to claim 1 including at least about 3 wt. % ofsaid colorant.
 11. A composition according to claim 1 comprising atleast about 1 wt. % of softening agent.
 12. A composition according toclaim 1 consisting essentially of:(A) about 10 to about 40 wt. % of saidfilm-forming resin; (B) about 3 to about 40 wt. % of said modifier; (C)0 to about 45 wt. % of said colorant; (D) about 1 to about 5 wt. % ofsoftening agent; and (E) about 10 to about 40 wt. % water.
 13. Acomposition according to claim 12 including about 3 to about 45 wt. % ofsaid colorant.
 14. A composition according to claim 1 including about 20to about 40 wt. % of said modifier.
 15. A composition according to claim14 including about 30 to about 40 wt. % of said modifier.
 16. Acomposition according to claim 12 including about 2 to about 4 wt. % ofsaid softening agent
 17. A composition according to claim 1 includingabout 1 to about 5 wt. % of softening agent.
 18. A composition accordingto claim 17 wherein the amounts of said modifier and said softeningagent are such that the composition includes at least about 3.5 times asmuch modifier as softening agent.
 19. A composition according to claim18 wherein said amounts are such that the composition includes at leastabout 5 times as much modifier as softening agent.
 20. A compositionaccording to claim 18 wherein said softening agent is an alcohol.
 21. Acomposition according to claim 18 wherein said softening agent is analkanolamine.
 22. A composition according to claim 20 wherein saidmodifier is a triazole, an aminotriazole or an azole.
 23. A water-basedembossing composition having a pH of about 6.5 to about 12 and aviscosity of about 600 to about 1000 cp for use in chemically embossinga foamable polymeric material having a blowing agent and an acceleratorfor the blowing agent incorporated therein consisting essentially of:(A)about 10 to about 40 wt. % of a film-forming vinyl or acrylic resindissolved or dispersed in said aqueous composition; (B) about 3 to about40 wt. % of a modifier which reduces the effectiveness of saidaccelerator so as to modify the activity of the blowing agent, saidmodifier being selected from the group consisting of triazoles, azoles,hydroquinone and thiourea and comprising particulate solids which aresubstantially insoluble and uniformly dispersible in the liquid mediumof the embossing composition and which have an average particle size ofno greater than about 100 microns; (C) about 1 to about 5 wt. % of asoftening agent for the modifier solids selected from the groupconsisting of amines and alcohols; (D) optionally, a colorant; and (E)about 10 to about 40 wt. % water;wherein the amount of modifier in thecomposition is at least about 3.5 times the amount of softening agent.24. A composition according to claim 23 including about 3 to about 45wt. % of said colorant.
 25. A composition according to claim 24 whereinthe amount of the modifier in the composition is at least about 5 timesthe amount of the softening agent.
 26. A composition according to claim24 having a pH of about 6.5 to about 9, a viscosity of at least about700 cp and consisting essentially of about 20 to about 40 wt. % of saidmodifier and about 2 to about 4 wt. % of said softening agent, andwherein the amount of the modifier in the composition is at least about5 times the amount of the softening agent.
 27. A composition accordingto claim 26 wherein said particle size of the modifier is about 10 toabout 75 microns.
 28. A composition according to claim 24 wherein saidmodifier is benzotriazole or tolyl triazole and including isopropylalcohol and/or diethylamino alcohol as a softening agent.
 29. Acomposition according to claim 28 wherein said particle size of themodifier is about 10 to about 75 microns.
 30. A water-based embossingcomposition which is effective in chemically embossing a foamablepolymeric material having azodicarbonamide blowing agent and zinc oxideaccelerator for the blowing agent incorporated therein and a viscosityof about 700 to about 1000 cp and consisting essentially of:(A) about 10to about 40 wt. % of a film-forming vinyl or acrylic resin dissolved ordispersed in said aqueous composition; (B) about 17 to about 40 wt. % ofbenzotriazole or tolyl triazole modifier which reduces the effectivenessof said accelerator so as to modify the activity of the blowing agentand which comprises particulate solids that are substantially insolubleand uniformly dispersible in the liquid medium of the embossingcomposition and that have an average particle size of about 40 to about75 microns; (C) about 2 to about 4 wt. % of an alcohol oralkylaminoalcohol softening agent for the modifier, the amount ofmodifier being at least about 5 times the amount of softening agent; (D)optionally, a colorant; and (E) about 10 to about 40 wt. % water.
 31. Acomposition according to claim 23 including at least about 17 wt. % ofsaid modifier.
 32. A composition according to claim 24 including atleast about 17 wt. % of said modifier.
 33. A composition according toclaim 31 including about 20 to about 40 wt. % of said modifier.
 34. Acomposition according to claim 32 including about 20 to about 40 wt. %of said modifier.
 35. A composition according to claim 33 includingabout 30 to about 40 wt. % of said modifier.
 36. A composition accordingto claim 34 including about 30 to about 40 wt. % of said modifier.
 37. Acomposition according to claim 23 wherein said particle size of saidmodifier is no greater than about 75 microns.
 38. A compositionaccording to claim 24 wherein said particle size of said modifier is nogreater than about 75 microns.
 39. A composition according to claim 37wherein said particle size is about 10 to about 75 microns.
 40. Acomposition according to claim 38 wherein said particle size is about 10to about 75 microns.
 41. A composition according to claim 39 whereinsaid particle size is about 40 to about 75 microns.
 42. A compositionaccording to claim 40 wherein said particle size is about 40 to about 75microns.
 43. A composition according to claim 31 wherein said particlesize of said modifier is no greater than about 75 microns.
 44. Acomposition according to claim 43 wherein said particle size of saidmodifier is about 10 to about 75 microns.
 45. A composition according toclaim 44 wherein said particle size of said modifier is about 40 toabout 75 microns.